Principles of Graphing Lab- Teacher Version
-
Upload
teachlabsci -
Category
Documents
-
view
227 -
download
0
Transcript of Principles of Graphing Lab- Teacher Version
-
8/6/2019 Principles of Graphing Lab- Teacher Version
1/16
Principles of Graphing Teacher Version
Key Concepts:
Understand the three components of a completed graph: (1) main title, (2) x and y-axis
titles, and (3) using correct units of measurement.
Distinguish between data representing independentand dependent variables.
Choose the most appropriate graph to useline, bar, orpiegiven different sets of data.
Analyzing and interpreting data that may be difficult to appreciate in a table format.
Introduction:
As data is gathered during a laboratory investigation or experiment, it is often helpful to not only
generate data tables, but graph the data for further analysis, comparison, and interpretation.
Graphs help to show relationships between sets of data that may be difficult to appreciate in a
table format only. These data are called variables.Independent variables can be changed,
altered, or modified by the scientist running the experiment.Dependent variables rely on the
conditions of the investigation. Dependent variables are dependent on the independent variables
and can be thought of as the outcomes of an investigation or experiment. Three types of graphs
will be used in this activity: line graphs, bar graphs, and pie graphs.Line graphs generally show
relationships between two sets of data in which the independent variable is continuous.Bar
graphs are used when there is no continuity from one piece of data to the next.Pie graphs, also
called pie charts, are particularly useful when parts or pieces of data will be compared to thewhole. Pie graphs normally include a key or legend describing the data each piece represents.
Example of a Line Graph
-
8/6/2019 Principles of Graphing Lab- Teacher Version
2/16
http://www.galeschools.com/research_tools/images/src/LineGraph.gif
Example of a Bar Graph
http://www.mathworksheetscenter.com/mathtips/bar2.gif
Example of a Pie Graph
-
8/6/2019 Principles of Graphing Lab- Teacher Version
3/16
http://www.swiftchart.com/pie_ex1.png
Materials:
Graph paper (several sheets per student)
Unlined, white computer paper (several sheets per student)
Protractors (at least one per student group)
Metric rulers (at least one per student group)
Calculators (or use of the calculating function on any cell phone)
Pencils and/or pens
Part 1: Pre-lab Questions
Answer the following pre-lab questions in the space provided.
1. What are variables and how do they affect scientific investigations?
Variables can be thought of as factors or items (data) scientists test in order to determinepotential cause and effect relationships in nature. Variables are part of the investigative
process and can be modified, altered, or controlled by scientists (independent variables) to
produce expected or unexpected outcome (dependent variables). In general, scientists
choose to keep all variables constant (controlled for) during an experiment except one,
which will be to focal point of the investigation.
-
8/6/2019 Principles of Graphing Lab- Teacher Version
4/16
2. Describe the difference(s) between independent and dependent variables.
A variable is independent when the scientist and not the events of the investigation control
it. Another common name for an independent variable is the manipulative variable, because
it is under direct control of the scientist. A variable is dependent because it depends on the
conditions of the investigation. Dependent variables are also referred to as respondervariables because they change in response to the manipulative, or independent, variables.
3. What are the three things that all graphs need to be complete?
a. Main title that briefly explains what the graph illustrates
b. X and Y-axis titles
c. Proper units of measurement for the X and Y-axis
Part 2: Making GraphsFor each of the following groups of data, make the appropriate kind of graph on a separate sheet
of paper. Be sure to include the three components that complete a graph. Line and bar graphs
should be drawn on graph paper, whereas pie graphs can be drawn on unlined paper if available.
1. Relationship of Water Temperature to the Heart Rate of Northwest Pacific Salmon
Advanced and Basic
Temperature in Degrees Celsius Heartbeats/Minute
10C 0/min
11C 8/min
13C 12/min
15C 16/min
21C 19/min
29C 23/min
31C 23/min
34C 20/min
38C 0/min
-
8/6/2019 Principles of Graphing Lab- Teacher Version
5/16
Water Temperature vs. Heart Rate of Northwest Pacific Salmon
0
3
6
9
12
1518
21
24
0 11 10 11 13 15 21 29 31 34 38
Temperature in Degrees Celsius
Heartbeats/Minute
2. U.S. Energy Expended in the Production of Wheat for 1975 and 2005 - Advanced
Input 1975 2005
Labor 3.0 kcal/m2 1.1 kcal/m2
Machinery 44.3 kcal/m2 103.9 kcal/m2
Gasoline 134.2 kcal/m2 196.4 kcal/m2
Nitrogen 14.2 kcal/m2 232.4 kcal/m2
Phosphorus 2.2 kcal/m2 11.2 kcal/m2
-
8/6/2019 Principles of Graphing Lab- Teacher Version
6/16
Potassium 1.2 kcal/m2 16.4 kcal/m2
Seeds 8.4 kcal/m2 15.3 kcal/m2
Irrigation 4.2 kcal/m2 8.2 kcal/m2
Insecticides 0.0 kcal/m2 2.5 kcal/m2
Herbicides 0.0 kcal/m2 2.5 kcal/m2
Other 15.1 kcal/m2 123.8 kcal/m2
-
8/6/2019 Principles of Graphing Lab- Teacher Version
7/16
U.S. Expended Energy to Produce Wheat in
1975 and 2005
0
20
40
60
80
100120
140
160
180
200
220
240
Labor
Machin
ery
Gasoline
Nitro
gen
Phosph
orus
Potas
sium Seeds
Irriga
tion
Insecticides
Herbicides
Other
Input
kcal/m
2
1975
2005
-
8/6/2019 Principles of Graphing Lab- Teacher Version
8/16
2. U.S. Expended Energy in the Production of Wheat for 2005 -Basic
Input 2005
Labor 1.1 kcal/m2
Machinery 103.9 kcal/m2
Gasoline 196.4 kcal/m2
Nitrogen 232.4 kcal/m2
Phosphorus 11.2 kcal/m2
Potassium 16.4 kcal/m2
Seeds 15.3 kcal/m
2
Irrigation 8.2 kcal/m2
Insecticides 2.5 kcal/m2
Herbicides 2.5 kcal/m2
Other 123.8 kcal/m2
-
8/6/2019 Principles of Graphing Lab- Teacher Version
9/16
U.S. Expended Energy to Produce
Wheat in 2005
0
20
40
60
80
100
120
140
160
180
200
220
240
Labor
Machin
ery
Gasoline
Nitro
gen
Phosph
orus
Potas
sium
Seeds
Irriga
tion
Insecticide
s
Herbicide
sOther
Input
kcal/m
2
-
8/6/2019 Principles of Graphing Lab- Teacher Version
10/16
3. Distribution of Butterfly Species in North America Advanced (graphed in degrees)
Species Name Number of
each Species
Fraction of Total
Students to fill in
Percent (%) of Total
Students to fill in
Degrees
Students to fill in
Tiger
Swallowtail
4,200 0.0046 0.46% 1.66
Black
Swallowtail
9,200 0.010 1.00% 3.60
Giant
Swallowtail
6,000 0.0066 0.66% 2.36
Pine White 12,500 0.0137 1.37% 4.93
Cabbage
White
70,000 0.0766 7.66% 27.59
Orange
Sulphur
6,500 0.0071 0.71% 2.56
Harvester 750,000 0.8211 82.11% 295.60
Blue Copper 5,000 0.0055 0.55% 1.97
Great Purple
Hairstreak
46,000 0.0504 5.04% 18.13
Silver-
Spotted
Skipper
4,000 0.0044 0.44% 1.58
Totals 913,400 ~ 1.0 ~ 100% ~ 360 degrees
** Fraction of Total = Number of each Species/Total # of all Species (decimal)
** Percent of Total = Number of each Species/Total # of all Species x 100
** Degrees = Number of each Species/Total # of all Species x 360
-
8/6/2019 Principles of Graphing Lab- Teacher Version
11/16
Distributions of Butterfly Species in North America
1.66o1.58o18.1o
1.9o
3.6o2.36o
4.93o 27.59o2.56o
295.6o
Tiger Swallowtail Black Swallowtail
Giant Swallowtail Pine White
Cabbage White Orange SulphurHarvester Blue Copper
Great Purple Hairstreak Silver-Spotted Skipper
** Note: Due to the small size of several of the pie pieces, the teacher may suggest that
students combine these pieces together to make graphing more effective. Students should
-
8/6/2019 Principles of Graphing Lab- Teacher Version
12/16
give a new name to this combined piece (e.g. other), add this new piece to their key or
legend, as well as list the name of each species of butterfly that make up the new piece.
-
8/6/2019 Principles of Graphing Lab- Teacher Version
13/16
3. Distribution of Butterfly Species in North America Basic (graphed in percents)
Species Name Number of each
Species
Fraction of Total
Students to fill in
Percent (%) of Total
Students to fill in
Tiger
Swallowtail
4,200 0.0046 0.46%
Black
Swallowtail
9,200 0.010 1.00%
Giant
Swallowtail
6,000 0.0066 0.66%
Pine White 12,500 0.0137 1.37%
Cabbage White 70,000 0.0766 7.66%
Orange Sulphur 6,500 0.0071 0.71%
Harvester 750,000 0.8211 82.11%
Blue Copper 5,000 0.0055 0.55%
Great Purple
Hairstreak
46,000 0.0504 5.04%
Silver-Spotted
Skipper
4,000 0.0044 0.44%
Totals 913,400 ~ 1.0 ~ 100%
** Fraction of Total = Number of each Species/Total # of all Species (report in
decimal form)
** Percent of Total = Number of each Species/Total # of all Species x 100
-
8/6/2019 Principles of Graphing Lab- Teacher Version
14/16
Distribution of Butterfly Species in North America
82%
1%
1%
1%0%0%5%1%
1%8%
Tiger Swallowtail Black Swallowtail
Giant Swallowtail Pine White
Cabbage White Orange Sulphur
Harvester Blue Copper
Great Purple Hairstreak Silver-Spotted Skipper
** Note: Due to the small size of several of the pie pieces, the teacher may suggest that
students combine these pieces together to make graphing more effective. Students should
give a new name to this combined piece (e.g. other), add this new piece to their key or
legend, as well as list the name of each species of butterfly that make up the new piece.
-
8/6/2019 Principles of Graphing Lab- Teacher Version
15/16
Part 3: Post-Lab Questions - Advanced
1. What is the independent variable for question number one?
The primary independent variable for question number 1 is the temperature of the water
as this can be controlled (either increased or decreased) by the scientist. Secondary
independent variables include: (1) number of fish, (2) species of fish, (3) age of fish, (4) sex
of fish, and (5) salt concentration of the water.
1a. The independent variable should be graphed on the X-axis.
1b. Line graphs show the relationship between two kinds of data in which the
independent variable is continuous.
2. Explain your selection of graph type for the data presented in question number two. In
other words, why did you select the type of graph and why does it illustrate the data given
the best?
In general, a bar graph is indicated for this set of data because the data is finite in nature
and there is no continuity from one piece of data to the next. Specifically, a double bar
graph is indicated because the question and data table indicate a comparison between two
years worth of information; 1975 and 2005.
2a. Bar graphs are used when there is no continuity or continuation from one piece
of data to the next.
3. Look at the data given in question number three. What would be an effective way tocheck your math calculations for percents, fractions, and degrees to make sure your graph
is correct? In other words, what should your totals add up to? (Hint: For degrees, think
about the shape your graph should be in).
A good way to check to see if calculations are done correctly is to individually add up all
the data from the three columnsFraction of Total, Percent (%) of Total, and
Degreesin the data table. If student calculations are within a few significant digits of
the expected totals for each category1.0, 100%, and 360 degrees respectivelythen
calculations were done correctly.
3a. Give a logical, reasonable explanation as to why your calculations for fractions,
percent, and degrees may not add up to exactly what you might have expected.
Normally, if student calculations are considerably off what is expected, a manual
error in using the calculator is to blame. If student calculations are only off by a few
significant digits (e.g. 360.76 degrees total instead of 360.0 degrees), generally these
-
8/6/2019 Principles of Graphing Lab- Teacher Version
16/16
types of errors are due to rounding variation. Students may round to the nearest
tenth, hundredth, or thousandth place which can affect the total slightly.
Part 3: Post-Lab Questions Basic
1. What is the independent variable for question number one?
Students should answer similarly to advanced lab answer given above.
1a. The independent variable should be graphed on the X-axis.
1b. Line graphs show the relationship between two kinds of data in which the
independent variable is continuous.
2. Why do you think individual bars on a bar graph are not connected to each other as data
points are in a line graph?
Bar graphs are used when there is no continuity or connection from one piece of data to the
next. Points on a line graph are generally connected because there is some kind of
relationship between the dependent variable and the independent variable which is
continuous in nature.
2a. Bar graphs are used when there is no continuity or continuation from one piece
of data to the next.
3. Look at the data given in question number three. What would be an effective way to
check your math calculations for percents and fractions to make sure your graph is
correct? In other words, what should your totals add up to?
Students should be able to offer suggestions similar to the projected answers of advanced
students listed above. Overall, basic students should understand that rounding errors may
slightly alter final calculations, but not enough to make their answers incorrect.
3a. Can you think of any other units of measurement pie charts can be graphed in
other than percentages? (Hint: Think about the shape of a pie graph).
Pie charts are graphed using the shape of a circle, which is comprised of 360
degrees. Thus, pie charts can also be graphed in degrees instead of percents which
are more commonly seen.
References:
Activity adapted from Making Graphs by MacMillan Publishing Co., Inc.